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Case File

CVE-2021-27239

HIGH · CVSS 8.8 EPSS 0.75% Public Exploit

Source: NVD + CISA KEV + EPSS (historical backfill) · Published 2021-03-29 · Last synced 2026-08-04

CyberRota Analysis

AI analysis pending.

Public Exploit Signal

A public exploit, PoC, GitHub repository or Metasploit reference was detected for this CVE.

Detected Signals
exploit

Note: these links are listed for security research and verification purposes only.

CVE
CVE-2021-27239
Severity
HIGH
CVSS
8.8
EPSS
0.75%

Original NVD Description

This vulnerability allows network-adjacent attackers to execute arbitrary code on affected installations of NETGEAR R6400 and R6700 firmware version 1.0.4.98 routers. Authentication is not required to exploit this vulnerability. The specific flaw exists within the upnpd service, which listens on UDP port 1900 by default. A crafted MX header field in an SSDP message can trigger an overflow of a fixed-length stack-based buffer. An attacker can leverage this vulnerability to execute code in the context of root. Was ZDI-CAN-11851.

Related CVEs

Other vulnerabilities affecting the same vendor(s)